Machine for dosing and filling thick liquids into bags of plastic material

ABSTRACT

An arrangement for metering and filling plastic bags with thin and thick liquids. A rotary member is intermittently indexed and carries a plurality of jaws equipped with suction means for holding the bag to be filled at the open edges. Metering cylinders fill the bag with a predetermined quantity of liquid, after which the bag is sealed through thermopulse welding. Indexing is accomplished through a maltese-cross device which is indexed and stopped through a cam-operated indexing mechanism. The indexing mechanism also operates the metering cylinders. A closure device closes the bag after filling and before indexing the rotary member to the next station.

I United States Patent [151 3,643,399 Bertoglio Web. 22, W72

[54] MACHINE FOR DOSING AND MILLING 3,070,932 1/ 1963 l-lofliger THICK LIQUIDS INTO BAGS @W g i'g e son e PLASTIC MATERIAL 3,492,785 2/ I970 Mancini ..53/282 [72] Inventor: Guido D. Wertoglio, Lugano-Viganello, a Y

Switzerland Primary Examiner-Robert L. Spruill [73] Assrgnee: Centra Anstalt, Vaduz, Liechtenstein and Sparrow [22] Filed: Sept. 2, 1969 [21] Appl. No.: 854,635 57 AWTRACT An arrangement for metering and filling plastic bags with thin fl Application Dam and thick liquids. A rotary member is intermittently indexed t, 31, 1 6 S l d 05 68 and carries a plurality of jaws equipped with suction means for DC 9 8 wnzer an 163 I holding the bag to be filled at the open edges. Metering cylin- 52 us. on .53 1187 53 266 the bag with Predetehhihed quantity quid, {51} mm. or. ..B65b 43/24, 1365b 3/32 which the hag is Sealed thwhgh hemwhuhe welding Index- [58] Field 6: Search ..53/l87, 188, 190, 266, 281, e is acmmphshed hwhgh a mahh'se-cwss device whih is 53 R32, 385, 386 indexed and stopped through a cam-operated indexing mechanism. The indexing mechanism also operates the meter- [56] References um ing cylinders. A closure device closes the bag after filling and before indexing the rotary member to the: next station. UNITED STATES PATENTS 2,969,632 lll9l Carew et al ......53/283 fiClaims, 11.1 Drawing Figures EET 5 OF 6 QQQ 60/00 .2. Elf/ MACHINE FOR DOSING AND FILLING THICK LIQUIDS INTO BAGS F PLASTIC MATERIAL BACKGROUND OF THE INVENTION The present invention relates to a machine for metering and filling thick and thin liquids into bags of plastic material. A frame rotating with intermittent motion and carrying at its periphery a plurality of jaws, has each jaw adapted to be opened and closed as well as to hold by suction the opening borders of the bag to be filled. A plurality of upper metering cylinders measure and then discharge the dosed filling liquid into a bag placed below. A device supplies the empty bags to the machine at the beginning of the filling cycle, and a pair of jaws provide for thermo-impulsewelding of the bags borders after the filling has been completed. A device discharges the filled bags.

The machine of the invention is characterized in that intermittent motion is imparted to the rotating frame by means of a maltese cross which is exactly maintained in its stop positions by a precision blocking device actuated by a first cam which is also responsible for the upand downward displacement of the metering cylinders. A second cam provides for the immediate closing of the bags after the filling, before the rotating frame is set into motion. For the filling of thick liquids into the bags, a suction and pressure pump with adjustable cubic capacity is provided instead of the dosing cylinders.

The accompanying drawings show a preferred embodiment of the machine of the invention.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a diagrammatic axial sectional view of the machine of the invention.

FIG. 2 is the relative plan view in reduced scale.

FIG. 3 is the plan view ofthe maltese cross.

FIG. 4 is a detailed view of the precision blocking device for the maltese cross.

FIG. 5 is the vertical axial sectional view of the machine in correspondence of the rotating frame.

FIG. 6 is the axial section through a metering cylinder.

FIG. 7 is the axial section through a distributing cock for the closed liquid.

FIG. 8 is a detailed view of the device for immediately closing each bag after the filling.

FIG. 9 is a plan view of the lever and cam system for the various control devices.

FIG. 10 is a view of the lever systems providing for the rapid closing of the jaws.

FIG. 11 is an axial sectional view of the suction and pressure pump for the thick liquids.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to FIGS. 1 and 2, the machine comprises the stationary mounting I supporting a frame tripwise rotating stepwise about the main shaft 3. At the periphery of the rotating frame 2, there are provided a plurality of jaws 4, 4, 4" etc., (FIG. 2) suited to hold by suction the opening sides of the bag to be filled. In the upper part of the machine as shown in FIG. I, there are provided a plurality of metering cylinders 6 suited to measure and then discharge the metered filling liquid into the bag below held by the jaws 4 but not shown.

The machine also comprises a device 7 for supplying the empty bags at the beginning of the filling cycle (FIG. 2), a pair of jaws 8 for thermoimpulse-welding the edges of the bag after the filling has been completed, and a device 9 for discharging the filled bags. The machine is characterized in that the intermittent motion is imparted to the rotating frame 2 by means ofa maltese cross 10 (FIGS. 1, 3 and 5) which is exactly maintained in its stop positions by a precision blocking device 11, I2 (FIGS. 4, 5), a so-called index," controlled by a first cam 13 (FIG. 1) which also serves to transmit an upward and downward motion to the metering devices 6 over lever systems 15 and 16 (FIGS. 1 and 5).

A second cam 17 (FIG. 1) serves to provide for the rapid closing of the filled bag before the rotating frame 2 starts its rotation. This is explained further below.

The cams 118, I9, 20 (FIGS. 1 and 5) mounted on the secondary shaft SI parallel to the main shaft 3, respectively, control the introduction of the empty bags and the instantaneously thermowelding jaws 8.

The intermittent motion is imparted to the rotating frame 2, as already mentioned, by the maltese cross I0 (FIG. 3) adapted to receive therein the pivot 38 carried by the disc 39 rotating together with the pivot 51 (FIGS. I and 5).

In its lower portion the maltese cross 10 is provided with tapered recesses 112 (FIG. 5) adapted to receive the end of the pin lll (FIGS. 1 and 4) actuated by the lever 40 controlled by the cam 13 so as to stop, in the very exact reached position, the said maltese cross and therewith the: rotating frame 2. In this way it is certain that the jaws 4, 4 and 4" etc., and the various members carried by the rotating frame 2 will take up their exactly defined and desired positions.

Since a jet of liquid could possibly spout from the filled bag by inertia when the rotating frame starts moving, provision is made for a device to close the bag before rotation is started. Such a device is made up by the recess 53 in the disc 29 (FIGS. 1, 8 and 10) having the follower means 54 (FIG. 8) penetrating therein and acting with its tip 54 on the pivot 56, thereby closing the jaws 4 and therefore the bag before the frame 2 starts rotating.

FIG. I] shows the device for feeding exactly metered quantities to the various bags case the liquids to be filled in are very thick.

For this purpose, a double-action pump is provided having a cylinder provided with a piston '71 actuated by a connecting rod 72 and a crank arm 73. This crank arm is adjustable to vary the stroke of the piston 72 and hence the volume of the liquid.

In this case the metering cylinders 6 of the machine are left out of use, and it will be the pump which directly feeds over the distributors 21 (FIGS. 6, 7) the metered liquid into the bags.

In operation, the maltese cross 10 cooperating with the pivot 38 carried by the disc 39 is driven by the motor through the shaft 51. As a result intermittent motion is applied to the rotating frame 2. When the maltese cross It] reaches each stop position, the pin 11 enters into tapered recess 12 and thereby assures that the jaws 4,4, 4"....fixed to the rotating frame 2, will assume their precise positions independent of the inertia of the moving parts and the high speed of the machine. For thin liquids, filling of the empty bags held by the jaws 4,4, 4".... occurs through the filling cylinders 6 which are lowered through the levers 16,15 and the cam 13. (FIG. 1). For thick liquids, on the other hand, filling occurs through the pump 70,71 (FIG. lll). Such filling occurs, therefore, under stationary conditions, and within a substantially short period of time. To prevent spilling of liquid from the bags that were filled, due to inertia when the frame 2 restarts moving, the bags are closed immediately before the frame starts moving. This is accomplished by closing the jaws 4 through the device consisting of recess 53 in the disc 29 (FIG. 8), and the follower means 54 as well as the tip 54.

What is claimed is:

1. An arrangement for metering and filling bags of plastic material with thin and thick liquids comprising in combination an indexed rotary member; a plurality of jaws carried by said rotary member at the periphery of said member with means for opening and closing said jaws; suction means on said jaws for holding open the edges of a bag to be filled; a plurality of metering cylinders above said bag to be filled for metering and dispensing liquid into said bag to be filled; bag feed means in proximity to said rotary member for supplying empty bags for filling; welding jaw means for thermo-pulse-welding said edges of said bag after filling said bag; removal means for removing said bag after filling and welding closed said bag; a substantially maltese-cross-shaped device actuating intermittently said rotary member; indexing means for indexing and stopping said device at predetermined angular positions for predetermined intervals, said rotary member being stationary while said bag is filled; means linking said indexing means to said metering cylinders for actuating said cylinders; closure means for closing said bag after filling and before moving said rotary member by said indexing means to a subsequent position; and suction and pressure pump means with adjustable volume capacity for filling said bag with thick liquids.

2. The arrangement as defined in claim 1 wherein said device has a plurality of recesses, said indexing means comprising a cam; a lever actuated by said cam; and pin means moved by said lever into said recesses for stopping said device at predetermined angular positions.

3. The arrangement as defined in claim 1 wherein said closure means comprises a disc with a plurality of recesses; follower means for penetrating said recesses, the tip portion of tributing liquid from said pump means.

6. The arrangement as defined in claim 1, including cam means in said indexing means for stopping said device and actuating said metering cylinders; and auxiliary cam means in said closure means for closing said bag after filling. 

1. An arrangement for metering and filling bags of plastic material with thin and thick liquids comprising in combination an indexed rotary member; a plurality of jaws carried by said rotary member at the periphery of said member with means for opening and closing said jaws; suction means on said jaws for holding open the edges of a bag to be filled; a plurality of metering cylinders above said bag to be filled for metering and dispensing liquid into said bag to be filled; bag feed means in proximity to said rotary member for supplying empty bags for filling; welding jaw means for thermo-pulse-welding said edges of said bag after filling said bag; removal means for removing said bag after filling and welding closed said bag; a substantially maltesecross-shaped device actuating intermittently said rotary member; indexing means for indexing and stopping said device at predetermined angular positions for predetermined intervals, said rotary member being stationary while said bag is filled; means linking said indexing means to said metering cylinders for actuating said cylinders; closure means for closing said bag after filling and before moving said rotary member by said indexing means to a subsequent position; and suction and pressure pump means with adjustable volume capacity for filling said bag with thick liquids.
 2. The arrangement as defined in claim 1 wherein said device has a plurality of recesses, said indexing means comprising a cam; a lever actuated by said cam; and pin means moved by said lever into said recesses for stopping said device at predetermined angular positions.
 3. The arrangement as defined in claim 1 wherein said closure means comprises a disc with a plurality of recesses; follower means for penetrating said recesses, the tip portion of said follower means controlling the closing of said plurality of jaws holding said bag.
 4. The arrangement as defined in claim 1 wherein said suction and pressure pump means comprises a piston and connecting rod; crank means for reciprocatingly actuating said piston; means for adjusting the crank arm of said crank means for varying the volumetric capacity of said pump means, said pump means directing said liquid into said bag to be filled.
 5. The arrangement as defined in claim 3 including distributing cock means connected to said pump means for distributing liquid from said pump means.
 6. The arrangement as defined in claim 1, including cam means in said indexing means for stopping said device and actuating said metering cylinders; and auxiliary cam means in said closure means for closing said bag after filling. 